An IC socket is used in an electronic circuit of for example a computer etc., where exchange or change of number of IC devices is expected, as a kind of mounting connector for electrically connecting an IC device and the electronic circuit through a plurality of contacts built into the IC socket while supporting the IC device in a detachable manner. Further, there are known test IC sockets used when running conduction tests or other electrical tests on IC devices before mounting in electronic apparatuses.
Among conventional IC sockets, one is known configured so as to place the IC device on an electrically insulating housing in a state pressing it against the plurality of contacts built into the housing so as to make the plurality of leads of the IC device abut against and connect with the contact parts of the corresponding contacts by a predetermined contact pressure. For example, Patent Document 1 discloses an IC socket provided with an electrically insulating housing having a support for supporting an IC device, a plurality of contacts providing contact parts elastically displaceable at the support and built into the housing, a plurality of pressing members for pressing the IC device supported at the support so as to make the plurality of leads of the IC device abut against the contact parts of the corresponding contacts, a biasing mechanism for generating a pressing force for pressing the IC device at the pressing member, and an operating member for turning and operating the pressing member on the housing.
Each of the plurality of pressing members provided at the IC socket is pivotably attached to the housing through a pivot and has a pressing surface for pressing the IC device against an end away from the pivot. These pressing members are arranged around the support with their pressing surfaces facing the support sides and can be synchronously pivoted between closed positions applying pressing forces to the IC device supported at the support from the pressing surfaces and open positions moving the pressing surfaces away from the IC device. Further, the operating member is provided with a cover arranged to be able to move in parallel in a direction approaching or moving away from the housing. The cover is a frame-shaped member having a center opening and is designed to enable the IC device to be inserted into or taken out of the support of the housing through that center opening. Further, the biasing mechanism is provided with a plurality of spring members for elastically biasing the cover in a direction moving away from the housing and a plurality of operating pins for transmitting the spring forces applied to the cover from the spring members to the individual pressing members. Each operating pin is provided at the other end of each pressing member at the side opposite to the pressing member across from the pivot and is pivotably connected with the cover.
In the above configuration, in the state with no external force applied to the cover, the cover is held at a position away from the housing due to the biasing forces of the plurality of spring members. The plurality of pressing members are arranged at closed positions where the pressing surfaces are brought close to the support of the housing (or operating positions of the pressing surfaces) due to the relative positional relationship among the operating pins, the pivots, and the pressing surfaces. If pressing in the cover in the direction approaching the housing against the biasing forces of the spring members from this state, the pressing members will turn about the pivots and reach the open positions where the pressing members are moved away from the support (or nonoperating positions of pressing surfaces). In this way, the pressing members are linked with the parallel displacement of the cover with respect to the housing and turn in a lever manner about the pivots between the closed positions and open positions.
When using the above IC socket, an IC device is inserted in the support of the housing of the IC socket mounted on a circuit board through the center opening of the cover in the state with the plurality of pressing members arranged at the open positions (that is, the states pressing in the cover). Next, the external force on the cover is released, the cover is made to move in parallel by the biasing forces of the spring members, and the pressing members are made to pivot to the closed positions linked with this. Due to this, the pressing members apply the spring forces of the spring members, transmitted through the operating pins from the cover to the pressing members, to the IC device when their pressing surfaces are in the operating positions and fixedly hold the IC device on the support. As a result, the plurality of contacts receive pressing forces from the plurality of leads of the IC device and elastically deform and the individual leads and contact parts of the contacts are brought into abutment under predetermined contact pressures to be electrically connected.
Note that IC sockets having lever type pressing members similar to the above are also disclosed in for example Patent Document 2 and Patent Document 3. In the IC sockets of Patent Documents 2 and 3, a plurality of links are interposed between the cover and a plurality of pressing members in a manner displaceable with respect to both. The pressing members have elongated holes at the opposite sides to the pressing surfaces across the pivots and receive shafts at first ends of the links connected to the covers at the other ends. Due to this, the pressing members turn in a lever manner about the pivots between the closed positions and open positions linked with the parallel displacement of the cover with respect to the housing through the links. Further, the spring forces of the spring members biasing the cover in a direction moving away from the housing are transmitted through the links to the pressing members and are applied to the IC device from the pressing surfaces as pressing forces.
[Patent Document 1] Japanese Unexamined Patent Publication (Kokai) No. 2003-115361
[Patent Document 2] Japanese Unexamined Patent Publication (Kokai) No. 2003-168532
[Patent Document 3] Japanese Unexamined Patent Publication (Kokai) No. 2003-187937